我们知道在App Store中几乎所有软件都设计到账户的登入，而我们最常见的就是QQ，微信，在没有踏入程序员这条不归路之前，看到一个个的界面都感觉好高大上的样子。

在学习的过程中，自己就照着手机上面APP自己比较好奇的界面实现了一下，今天分享一下关于QQ登入界面，完全纯代码，实用StoryBoar太麻烦，个人比较喜欢用代码实现，而几乎所有登入界面几乎都是一样的，只是图标不同，或者还会有其他的拓展功能，不过这里都会了其他的纳豆不是事儿。

废话不多说，直接上代码

import UIKit class ViewController: UIViewController {        /// 定义属性var QQNumber = UITextField()var PassNumber = UITextField()            override func viewDidLoad() {                self.view.backgroundColor = UIColor.whiteColor()        super.viewDidLoad()           // 添加头图片        [self .addAllSubViews()];    }     // 添加所有子控件    func addAllSubViews(){            /// 头像       /var headImage = UIImageView(frame: CGRectMake(50, 30, 220, 200))        headImage.image =  UIImage(named:"QQ.png")        self.view.addSubview(headImage)                /// QQ号输入提示       // var phoneText = UILabel(frame: CGRectMake(30, 240, UIScreen.mainScreen().bounds.size.width-60, 30))       // phoneText.text = "请输入QQ号"        //self.view.addSubview(phoneText)                /// QQ号输入框        var QQNumber = UITextField(frame: CGRectMake(30, 270, UIScreen.mainScreen().bounds.size.width-60, 30))        QQNumber.placeholder = "请输入QQ号"        QQNumber.layer.borderWidth = 1        QQNumber.layer.borderColor = UIColor.lightGrayColor().CGColor        QQNumber.layer.cornerRadius = 5        QQNumber.keyboardType = UIKeyboardType.NumberPad        self.view.addSubview(QQNumber)        self.QQNumber = QQNumber                /// 密码输入提示        //var passText = UILabel(frame: CGRectMake(30, 300, UIScreen.mainScreen().bounds.size.width-60, 30))        //passText.text = "请输入密码"        //self.view.addSubview(passText)                /// 密码输入框        var PassNumber = UITextField(frame: CGRectMake(30, 330, UIScreen.mainScreen().bounds.size.width-60, 30))        PassNumber.placeholder = "请输入密码"        PassNumber.layer.borderWidth = 1        PassNumber.layer.borderColor = UIColor.lightGrayColor().CGColor        PassNumber.layer.cornerRadius = 5        self.view.addSubview(PassNumber)        self.PassNumber = PassNumber                /// 密码找回        var button = UIButton(frame: CGRectMake(200, 360, 120, 30))        UIButton.buttonWithType(UIButtonType.Custom)        button.setTitle("忘记密码", forState: UIControlState.Normal)        button.setTitleColor(UIColor.lightGrayColor(), forState: UIControlState.Normal)        self.view.addSubview(button)        button.addTarget(self, action: "onClick", forControlEvents: UIControlEvents.TouchUpInside)           }        /// 密码找回方法实现    func onClick(){            ///找回密码提示    UIAlertView(title: "温馨提示", message: "新密码已发送至手机上", delegate: nil, cancelButtonTitle: "确定", otherButtonTitles: "取消").show()    }    /**    点击界面键盘辞去第一响应者    */    override func touchesBegan(touches: NSSet, withEvent event: UIEvent) {               self.QQNumber.resignFirstResponder()        self.PassNumber.resignFirstResponder()    } }